CN102283723B - Method for quickly molding biological ceramic microsphere artificial bone scaffold with controllable mechanical property - Google Patents

Abstract

The invention discloses a rapid prototyping method of a bioceramic microsphere artificial bone scaffold with controllable mechanical properties. The method first divides the CAD model of the artificial bone scaffold into N parts of equal-spaced two-dimensional cross-sectional graphics; and then according to the generated two-dimensional cross-section Graphics, control the scanning movement of the nozzle, and selectively spray the instant-drying binder onto the surface of the bioceramic microsphere layer, so that the bioceramic microspheres are superimposed and bonded in layers, and accumulated to form a three-dimensional artificial bone scaffold structure. By controlling the spraying amount of the instant-drying adhesive, the bond strength between the bioceramic microsphere layers can be controlled, thereby controlling the mechanical properties of the entire artificial bone scaffold; by adjusting the diameter of the bioceramic microsphere and the instant-drying adhesive The spraying amount can obtain artificial bone scaffolds with different porosity; the adhesive used in the present invention is a medical instant-drying adhesive, which ensures the biocompatibility and molding efficiency of the artificial bone scaffold.

Description

The biological ceramic microsphere artificial bone scaffold quick molding method of controlled mechanical property

Affiliated field

The present invention relates to a kind of manufacture method of biological ceramic microsphere artificial bone scaffold, particularly the biological ceramic microsphere artificial bone scaffold quick molding method of controlled mechanical property.

Prior art

In the operations such as damaged, the bone remodelling of the various bones for the treatment of, need to implant or fill autologous bone or allograph bone at the damaged position of bone and reach the object of healing, make skeleton recover as soon as possible its integrity and seriality, to obtain normal mechanical property.In prior art, clinically the repair materials of large section of bone is had to autologous bone, allograph bone, tissue engineered bone etc.Adopt autologous bone, advantage is without immune rejection, but has the shortcoming that source is limited, get bony site and often leave over the complication such as chronic pain.Adopt allograph bone, advantage is cortical bone or the spongy bone that enough difformity sizes can be provided, and but has the shortcoming that easily causes immunoreation, infectivity virus disease.Therefore, nineteen ninety-five Crane etc. has systematically proposed the basic conception of tissue engineered bone, utilizes the principle of tissue engineering and method to carry out repair and reconstruction to defective bone tissue.

Desirable bone substitute should meet following requirement: 1, have good biocompatibility with tissue, without immunogenic, react; 2, close with people's biomechanics of bone performance, and there is certain intensity and support force; 3, good three-dimensional microcosmic structure, guarantees that culture fluid and blood can enter bone internal stent, and is easy to molding; 4, good osteoinductive; 5, there is suitable surface physicochemical property, and can be absorbed and substitute by host bone tissue; 6, draw materials conveniently, be easy to a large amount of making.Therefore,, during manufacturing artificial bone support, except considering its biocompatibility, three-dimensional geometrical structure, surface physicochemical property, the very important point, considers whether its mechanical property can meet the requirement close with patient people's biomechanics of bone performance exactly.

Based on speed forming method, prepare the important technology of preparing of one that artificial bone scaffold is artificial bone scaffold.At present, the quick molding method of artificial bone scaffold mainly contains: Stereolithography technique, lamination manufacture, selective laser sintering, three dimensional printing shaping, Fused Deposition Modeling etc.The rapid shaping technique of the artificial bone scaffold based on spraying technique has: screw extruding sprays, piston pushes injection, Pneumatic extrusion injection, droplet ejection technology, laser aiming direct writing technology, Electrospinning, dips in a nanometer etching technology etc.

The artificial bone scaffold quick molding method that the present invention proposes is based on rapid shaping technique, but is not exclusively equal to the quick molding method of above-mentioned existing artificial bone scaffold.The quick molding method of the artificial bone scaffold that the present invention proposes, is that dry wink binding agent is sprayed onto on biological ceramic microsphere layer, is bondd, and realizes the accumulation molding of artificial bone scaffold.

Patent of invention 200410030652.6 discloses a kind of CT assisted bone imitated producing artificial bone method.The method scans skeleton prototype by CT, obtain the density information image of geometric shape information, interior three-dimensional vesicular texture information and the three-dimensional space position of skeleton, this three-dimensional information image is carried out to quantification treatment, obtain binary image, recycling rapid shaping technique, realizes the accumulation molding of artificial bone scaffold.Be characterized in, can obtain accurate initial data, according to the result images molding to osteometry, produce the artificial bone that precision is high.Patent of invention 200410025965.2 discloses a kind of artificial bone bionic manufacturing process based on rapid shaping and stereo weaving.Be characterized in, application stereo weaving is coated with the microstructure of method structure artificial bone, can the artificial bone MCA of manufacturing be carried out pre-designed and be controlled.Patent of invention 200610105346.3 discloses a kind of dual-scale micro-structure artificial bone scaffold and preparation method thereof, the method is based on computer aided design cad and Introduction To Stereolithography, first prepare the resin die of artificial bone minus, the paraffin bead of filling certain diameter in mould suitably pressurizes, recharge biomaterial slurry, vacuum drying after cured, last, resin die and paraffin bead are removed in thermal decomposition, form the tubing of macro-scale and the spherical pore of micro-scale.Be characterized in, this support micro structure comprises that the ball of micro-scale connects the tubing of hole and macro-scale, spherical pore random distribution, and tubing can design in advance.

Above-mentioned three kinds of artificial bone scaffold manufacture methods based on rapid shaping all lay particular emphasis on the three-dimensional geometry form of artificial bone scaffold and the design of microstructure, do not consider the mechanical property of regulation and control artificial bone scaffold.So, the present invention proposes the biological ceramic microsphere artificial bone scaffold quick molding method of controlled mechanical property.The method is on the basis of existing artificial bone scaffold quick molding method, take the mechanical property of artificial bone scaffold after molding as design object, and a kind of novel artificial bone scaffold quick molding method proposing.

Summary of the invention

Existing artificial bone scaffold quick molding method, mainly considers artificial bone scaffold three-dimensional configuration and microstructure, and seldom considers its mechanical property.Can be handling in order to improve artificial bone scaffold mechanics, the present invention proposes a kind of biological ceramic microsphere artificial bone scaffold quick molding method of controlled mechanical property.

In order to achieve the above object, the technical solution used in the present invention is: a kind of biological ceramic microsphere artificial bone scaffold quick molding method of controlled mechanical property, by controlling the scanning motion of shower nozzle, dry wink binding agent is optionally sprayed onto to biological ceramic microsphere layer surface, thereby by biological ceramic microsphere layering stack bonding, pile up and mold three-dimensional artificial bone scaffold structure.Concrete steps are as follows:

Step 1, computer are processed artificial bone scaffold three-dimensional CAD model, and it is sequentially divided into two-dimensional section figure N part that spacing is Δ h from bottom to up, and i part sectional view area is A _i, the diameter that wherein size of Δ h is biological ceramic microsphere;

Step 2, the average consumption of setting dry binding agent of wink in every layer of biological ceramic microsphere unit are are q _i;

Step 3, N part two-dimensional section figure that step 1 is generated are sent into rapidform machine;

Step 4, i=1, on forming worktable, uniform spreading last layer biological ceramic microsphere is also used powder-laying roller compacting;

Step 5, adjusting nozzle technological parameter, set main jet and count n _i, single-nozzle flow Q _i, a j main jet spraying time t _jand nozzle is to the spacing l of biological ceramic microsphere layer; Control shower nozzle track while scan, according to i part sectional view, selectivity sprinkling wink, dry binding agent was to i layer biological ceramic microsphere; To described wink, the requirement of dry binding agent is: be 10 hardening time ^s-60 ^s, viscosity low be enough to be applicable to spray; And then uniform spreading last layer biological ceramic microsphere is also used powder-laying roller compacting, formation i+1 layer; Wherein, Q _i, t _jshould meet following relation:

$q_i=\underset{j=1}{\overset{n_i}{\mathrm{\Σ}}}{Q}_i\×t_j/A_i$

Step 6, judge i value, if i < is N-1, i=i+1, repeating step 5; Otherwise, enter next step;

Step 7, rack making are complete, take out support, and support is carried out to post processing.

The invention has the beneficial effects as follows: first, the present invention sets different q by the sprinkling amount of controlling dry binding agent of wink _ivalue, control the adhesion strength between biological ceramic microsphere layer, and then control the mechanical property of whole artificial bone scaffold, thereby a kind of quick molding method that meets the controlled mechanical property of artificial bone scaffold is provided, in clinical practice, can have met and cause the different requirement to artificial bone scaffold mechanical property because of patient individual difference.Secondly, the present invention can by regulate biological ceramic microsphere diameter and wink dry binding agent sprinkling amount, obtain the artificial bone scaffold of different porosities.Moreover, the present invention is based on rapid shaping principle, shaping efficiency is high, preparation technology's flow process is simple, and stock utilization is high.

Accompanying drawing explanation

Fig. 1 is the artificial bone scaffold sample that adopts quick molding method of the present invention to produce.

Concrete embodiment

The biological ceramic microsphere artificial bone scaffold quick molding method of controlled mechanical property in the present embodiment, the rapid molding device of selecting at least comprises following ingredient: X-Y workbench, forming worktable, powder-laying roller device.The downward shower nozzle of nozzle is housed on X-Y workbench, by driven by servomotor control shower nozzle, in XY plane, carries out scanning motion.Forming worktable, should comprise shaping work cylinder, feed working cylinder.Support completes the processing of support in shaping work cylinder, and shaping work cylinder is at every turn along the distance of a microsphere diameter of Z-direction decline, and after rack forming completes, shaping work cylinder rises, and takes out support.Shaping work cylinder, along the lifting of Z-direction, is driven and is controlled by servomotor.Feed working cylinder is used to provide the biological ceramic microsphere material of molding and support, and it is driven and controlled by servomotor along the lifting of Z-direction.Powder-laying roller device, comprises powder-laying roller and drive system thereof, and its effect is that biological ceramic microsphere material is paved equably on shaping work cylinder.

In this embodiment, selecting diameter is that the hydroxyapatite micro-sphere of 0.5 ± 0.2mm is as moulding material; Select Kang Paite medical adhesive as dry binding agent of wink, be 15s hardening time; Select XAAR128/80-W piezo jets, nozzle number is 128; Rapid shaping is made the cuboid artificial bone scaffold of a 10mm × 10mm × 2.5mm.

It is 10mm × 10mm, the high artificial bone scaffold cad model for 2.5mm that step 1, computer are processed bottom surface, by its from bottom to up order be divided into 5 parts, the two-dimensional section figure of separation delta h=0.5mm, every part of sectional view area A _i=100mm ²;

Step 2, set the average consumption q of dry binding agent of wink in every layer of hydroxyapatite micro-sphere unit are _i=0.0004ml/mm ²;

Step 3,5 parts of two-dimensional section figures that step 1 is generated are sent into rapidform machine;

Step 4, i=1, on forming worktable, uniform spreading last layer hydroxyapatite micro-sphere is also used powder-laying roller compacting;

Step 5, adjusting nozzle technological parameter, set main jet and count n _ibe 70, single-nozzle flow Q _ibe 4.4 × 10 ^-4the spraying time t of ml, each main jet _jbe 1.30s, nozzle is 1mm to the spacing h of hydroxyapatite micro-sphere layer; According to i part sectional view, control the track while scan of shower nozzle, selectivity sprinkling wink, dry binding agent was to i layer hydroxyapatite micro-sphere; And then uniform spreading last layer hydroxyapatite micro-sphere is also used powder-laying roller compacting, formation i+1 layer;

Step 6, judge i value, if i < 4, i=i+1, repeating step 4; Otherwise, enter next step;

Step 7, rack making are complete, take out support, and support is carried out to post processing, remove excess stock, reclaim unnecessary hydroxyapatite micro-sphere to reuse;

The comprcssive strength of the artificial bone scaffold sample that this embodiment is made is 4.80MPa;

In order to verify, set different q _ivalue can be produced the artificial bone scaffold of different mechanical properties, and the method for also using the present invention to propose is produced kinds of artificial bone support under different technology conditions, and its corresponding comprcssive strength is as shown in table 1.

Relation between table 1 support comprcssive strength and binding agent sprinkling amount

Claims (1)

1. A rapid prototyping method of bioceramic microsphere artificial bone scaffold with controllable mechanical properties, is characterized in that, comprises the steps: Step 1. The computer processes the three-dimensional CAD model of the _artificial bone scaffold, and sequentially divides it into N parts of two-dimensional cross-sectional graphics with a distance of Δh from bottom to top. diameter of; Step 2, setting the average amount of instant-drying binder per unit area of each layer of bioceramic microspheres as q _i ; Step 3, sending N parts of two-dimensional cross-sectional graphics generated in step 1 into the rapid prototyping machine; Step 4, i=1, evenly spread a layer of bioceramic microspheres on the forming table and compact them with a powder spreading roller; Step 5. Adjust the technological parameters of the nozzles, set the number of working nozzles n _i , the flow rate Q _i of a single nozzle, the spraying time t _j of the jth working nozzle, and the distance l between the nozzle and the bioceramic microsphere layer; control the scanning trajectory of the nozzle, according to The i-th cross-sectional figure selectively sprays the instant-drying adhesive onto the i-th layer of bioceramic microspheres; the requirements for the instant-drying adhesive are: the curing time is 10s-60s, and the viscosity is low enough to be suitable for spraying; then Then evenly spread a layer of bioceramic microspheres and compact them with a powder spreading roller to form the i+1th layer; among them, Q _i and t _j should satisfy the following relationship:

Step 6. Determine the value of i, if i<N-1, then i=i+1, repeat step 5; otherwise, go to the next step; Step 7. After the bracket is made, take out the bracket and perform post-processing on the bracket. the

Images